This document discusses the morphology and modifications of plant roots. It begins by defining morphology and describing the basic structure and functions of roots. It then discusses different root types including tap roots, fibrous roots, and adventitious roots. The document focuses on various modifications of roots for storage, respiration, mechanical support, and other vital functions. Examples are provided for different root modifications like tuberous roots, stilt roots, haustoria, and assimilatory roots. Key morphological features and functions of roots are summarized along with example questions asked in previous examinations.

1. Morphology of Root
Kalariya Manisha V.
M. Pharm(Herbal Drug Technology)
B.K.M.G.P.C., Rajkot

2.  Morphology deals with the study of forms
and features of different plant organs such
as roots, stems, leaves, flowers, seeds and
fruits.
 It includes shape, size, colour, odour, taste
etc. of various plant organs their
modification.
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Introduction

3. Introduction
 The root is descending organ of the plant,
and is originally the direct prolongation of
radicle of the embryo.
 It grows downwards, fixes the seedling and
later the plant as a whole to the ground,
and absorb raw food materials from the
soil particles.
 It is non green in color, without nodes and
internodes, with no leaves or buds.
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4. Region of root
Root cap
 The tip of the root is
covered by a cap like
structure called the root
cap.
 It protects the delicate
growing point of root
 Eg. Banyan root
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5. Different kinds of root
Normal root
 All the roots which arise at the
base of the stem from the
radicle are called normal roots.
Adventitious root
 Roots which do not arise from
their normal point of origin i.e.
form the base of the stem but
they are produced from part of
stem, branch or leaf.
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6. Kinds of root system
Tap root
 When the main root is
the direct prolongation
of the radicle is called
primary root.
 If the primary root
continue to grow
stronger than its
secondary branches is
called tap root
 Eg. Datura root
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7. Kinds of root system
Fibrous branching tap root
 When the primary root is
short and lateral roots are
thin, long, and fibrous is
called fibrous branching tap
root.
 Eg. Sunflower root
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8. Kinds of root system
Fibrous root
 When there is no tap
root but a large number
of fibrous root arise
from the base of the
stem is called fibrous
root.
 Eg. Grass
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9. Functions of root
Mechanical
 Fixation of plant into the soil.
Physiological
 Absorption of water, minerals and raw material from
the soil.
Special functions
 Storage of food, water and other materials. Eg. carrot,
beet
 Some root provide support. Eg. Banyan
 Respiratory function
 The root of gulvel do photosynthesis 9

10. Modification of tap root for
storage
Conical
 When the root is broad
at the base and
gradually tapers
towards the apex like
cone is called conical
root
 Eg. Carrot
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11. Modification of tap root for
storage
Fusiform
 When it is swollen in
the middle and
gradually taper at the
both end.
 Eg. Raddish
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12. Modification of tap root for
storage
Napiform
 When it is considerably
broad at the upper part
then become rounded
and abruptly tapering
towards the lower end.
 Eg. Beet
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13. Branched root modified for respiration
Pneumatophores root
 Plants growing in marshy places and
salt lakes, develop special kind of
roots for breathing, called
‘pneumatophores’ or respiratory
roots.
 These root rise vertically upwards &
come out of the water like conical
spikes around the trees.
 These root are provided with
numerous pores toward the upper
end, called ‘lenticels’.
 Lenticels through which air is taken
in for respiration. Eg. Rhizophora
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14. Modification of adventitious
root for storage
Tuberous root
 Adventitious roots are
generally fine and fibrous as
in grass but often they
become thick, swollen and
fleshy by storage of food
material.
 They are without any
definite shape and produced
singly.
 Eg. Sweet potato
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15. Modification of adventitious
root for storage
Fasciculated tuberous root
 When large number of roots
are arises from the common
point at the base of the stem
and all become fleshy and
swollen.
 Eg. Asparagus root
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16. Modification of adventitious
root for storage
Palmated tuberous root
 When a double tuberous
root gives out branching
process like the finger
from the palm.
 Eg. Orchis
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17. Nodulous root
 When the slender root
becomes suddenly
swollen at the apex, it
is said to be nodulose
root.
 Eg. Turmeric, Arrow
root
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Modification of adventitious
root for storage

18. Moniliform or Beaded
root
 When there are some
swellings in the root
at frequent intervals,
it is called as
‘moniliform’ or
‘beaded’ roots.
 Eg. Indian spinach,
Bitter gourd 18
Modification of adventitious
root for storage

19. Annulated roots
 When the roots have a
series of ring-like
swelling on its body,
it is called as
‘annulated’.
 Eg. Ipecac
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Modification of adventitious
root for storage

20. Modification of adventitious
root for mechanical support
Prop or stilt root
 A no. of roots are produced from
the main stem or branches and
grow vertically or obliquely
downwards and penetrate into the
soil.
 Gradually they get stouter and act
as pillars for supporting the main
stem or whole plant. Such roots
are known as prop or stilt root.
 Eg. Banyan
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21. Modification of adventitious
root for mechanical support
Climbing root
 The plant produce
climbing root form their
nodes and often
internodes, by means of
which they attach
themselves to their support
and climb it.
 Eg. Piper betel
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22. Modification of adventitious
root for vital functions
Sucking roots or haustoria
 There are some plants which
grow on the branches of the
other plant and obtain their food
by sending special roots called
the sucking roots or haustroia
into the substance of the host
plants and absorb the
nourishment form them. Such
plants are called parasitic
plants.
 Eg. Cuscuta
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23. Modification of adventitious
root for vital functions
Respiratory roots
 In aquatic plants, the
floating branches develop
adventitious roots, which
are soft, light, spongy and
colourless.
 They develop above the
level of water and serve to
store air and facilitate
respiration.
 Eg. Jussiaea repens
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R
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24. Modification of adventitious
root for vital functions
Epiphytic roots
 The orchids which grow on
branches of trees, Such plants are
known as epiphytes.
 They never suck the supporting
plants.
 They develop special roots which
hung freely in the air.
 Each hanging roots are
surrounded by spongy tissue
called ‘velamen’. With these, the
hanging root absorbs moisture
from the air.
 Eg. vanda
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25. Modification of adventitious
root for vital functions
Assimilatory roots
 Branches of tinospora
climbing on
neighbouring trees
produce long, slender,
hanging roots which
develop chlorophyll
and turn green in
colour. These green
roots are assimilatory
roots.
 Eg. Chest nut 25

26. Questions asked in GTU Exam
 What is morphology? Define root and add
note on modification of roots for storage.
(GTU’10)
 Define terms with suitable examples for: 1)
Breathing roots, 2) Stilt root, 3) Parasitic
root, 4) Tap root. (GTU’10)
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